Like other species of the genus Candida, Candida albicans is a diploid fungus that grows both as yeast and filamentous cells. More specifically, C. albicans is a dimorphic fungus, which has both a yeast-like growth habit and a filamentous form consisting of both hyphae and pseudohypae. C. albicans exists as part of the normal microbial flora in humans, but can produce opportunistic infections ranging from topical infections such as oral thrush to life-threatening disseminated mycoses. In response to changes in its environment, C. albicans can transition from budding yeast to its filamentous morphology. The filamentous morphology is important for its virulence and causes both skin and mucosal infections. Quorum sensing has been identified as a phenomenon contributing to C. albicans' morphogenic transition from its conidial to filamentous form.
Quorum sensing systems have been found to coordinate virulence and biofilm development of pathogenic microorganisms. Manipulation of quorum sensing systems has been recently considered a promising strategy for developing antimicrobial agents since the manipulation of quorum sensing systems only inhibits the virulence but not the growth of microorganisms.
Farnesol is an acyclic sesquiterpene alcohol (a class of terpenes) that is naturally found in many different essential oils, including but not limited to citronella oil, neroli oil, cyclamen oil, lemon grass oil, tuberose oil, rose oil, musk oil, and balsam and tolu oil. Generally, farnesol is an acyclic sesquiterpene alcohol found as a colorless liquid. Farnesol is insoluble in water, but miscible with oils. Farnesol has been found to act as a quorum sensing inhibitor to decrease the rate that Candida albicans transitions from budding yeast to the filamentous form.
However, the practical use of farnesol as a quorum sensing inhibitor with respect to C. albicans is particularly difficult due to its insoluble nature in water. That is, it is difficult to apply farnesol to wipes or other materials for use, especially in a large-scale manufacturing environment. Additionally, it is difficult to incorporate farnesol within compositions (e.g., lotions) that can be used as a quorum sensing inhibitor, particularly when applied to the skin of a user.
As such, a need exists for a manner in which farnesol can be used as a quorum sensing inhibitor of C. albicans in a practical manner.